Apparatus for forming neck finishes on glass containers



P. H. PAYNE 3,015,911

APPARATUS FOR FORMING NECK FINISHES ON GLASS CONTAINERS Jan. 9, 1962 Original Filed Nov. 27, 1957 v 3 Sheets-Sheet 1 INVENTOR. Paul H. Pa

,9 TTGENEYS Jan. 9, 1962 P. H. PAYNE 3,015,911

APPARATUS FOR FORMING NECK FINISHES 0N GLASS CONTAINERS Original Filed Nov. 27, 1957 3 Sheets-Sheet 2 flm fi N 1 24 N4 M YIHIHIH /H W INVENTOR. Paul H. Payne P. H. PAYNE Jan. 9, 1962 APPARATUS FOR FORMING NECK FINISHES ON GLASS CONTAINERS 3 Sheets-Sheet 3 Original Filed Nov. 27, 1957 P l H [Al/\gENTOR.

Q5078 EZWZ/ United States Patent 3,015,911 APPARATUS FOR FORMING NECK FINISHES ON GLASS CONTAINERS Paul H. Payne, Bridgeton, NJ., assignor to Owens-11hnois Glass Company, a corporation of Ohio Original application Nov. 27, 1957, Ser. No. 699,254. Divided and this application Sept. 18, 1958, Ser. No.

7 Claims. (CI. 4968) The present invention relates to neck mold apparatus on glass forming machines for manufacturing glass containers, such as bottles, jars and the like, and more particularly to apparatus for prevention of out-of-round of neck finish of the containers manufactured by these machines and eliminate off-gauge finishes in such containers.

The present application is a division of my copendmg application, Serial No. 699,254, filed on the 27th day of November, 1957.

The invention is particularly applicable to the manufacture of wide mouth or intermediate neck size containers, as contrasted to narrow neck containers, but the invention need not be limited in its application to this Wide mouth containers are conventionally manufactured by the press and blow process, in which the initial step is that of pressing a parison from a gob of glass in a partible blank or parison mold and a partible neck mold, the latter defining the exterior contour of the neck finish of the finished container.

Pressing is accomplished by a reciprocating plunger operating through the center opening of the neck mold to press the glass against the blank mold and against the glass contacting surfaces of the neck mold. The plunger, when fully inserted in the blank, defines the interior molding surface of the neck finish. The formed parison has a finished neck portion and integral body blank which is conventionally transferred to a blow mold where the body blank is expanded by blowing to the finished shape of container.

At the time of the transfer to the blow mold, the glass in the neck finish is in process of setting-up or cooling to change its physical characteristics from a highly viscous plastic state, assimilating the viscosity of warm taffy, to a solid.

One of the difiiculties prevalent at this point in the process is that the neck finish, after the plunger is withdrawn from the neck mold, is distorted and develops an out-of-round configuration. Out-of-round of the neck, if it exceeds the established very narrow tolerances, results in oil-gauge ware unfit for commercial use. These tolerances are determined by the ability to apply a suitable closure and obtain an acceptable seal.

It has been found that out-of-round almost invariably occurs on a diameter of the neck finish that is displaced 90 from its mold seam diameter. This latter diameter is a diameter of the neck approximately on a vertical plane through the central axis of the container and is the plane at which the neck molds part or are opened and closed. It is generally the case, that after the glass in the neck has set-up, its mold seam diameter, due to greater shrinkage in setting-up, is less than the diameter normal to the mold seam. The degree of shrinkage during setting-up of the glass is believed attributable directly to the rate of cooling the glass. At the mold seam diameter, the mold seam tends to vent the air between the pressed glass and the glass contacting surface of the neck mold so that the glass and the metal of the mold have a more intimate contact than exists near the diameter norma1 to the seam. At this latter diameter, an air film ICC occurs between the glass and the metal, and since the metal of the mold is a better heat conductor than the air film, the result is that the glass is cooled at a higher rate and consequently sets up faster and shrinks to a greater extent adjacent the mold seam.

It is an object of the invention, therefore, to provide apparatus for differentially cooling the neck mold adjacent the diameter normal to the mold seam to give a comparable rate of cooling to that existing adjacent the mold scam and thereby equalize the shrinkage at both diameters to prevent out-of-round on the finished neck of the container.

Another object of the invention is to provide improved neck mold apparatus for circulating fluid through the neck mold adjacent its glass contacting surface in annular zones contained within the limits of an arc of a circle no greater than a quadrant of a circle centered at opposite sides of the neck on the diameter of the neck normal to the mold seam.

A further object of the invention is to provide apparatus for utilizing some blow air introduced through the neck mold during the final blowing step of the forming process in carrying out the aforementioned objects.

Other objects and advantages will become apparent to those skilled in the glass forming art from the following description, taken in conjunction with the annexed sheets of drawings, on which, by way of preferred example only, are illustrated three forms of the invention.

On the drawings:

FIG. 1 is a sectional elevational view of the first form of the invention on a neck mold assembly in position over a blow mold of a press and blow glass forming machine and shows the utilization of blowing air to cool part or the neck mold during blow forming process wherein a glass container is blown to shape.

FIG. 2 i a sectional elevational view of a guide ring for the neck mold assembly.

FIG. 3 is a sectional elevational view of the neck mold assembly with its partible neck ring partially open and illustrates one arrangement of the air passages in the neck ring.

FIG. 4 is a perspective view, partly in section, show ing a cut-away view of assembled neck mold assembly of a second form of the invention.

FIG. 5 is a plan view of the neck mold assembly, showing the neck rings closed and illustrates arrangement of the air passages of a third form of the invention.

FIG. 6 is a partial elevational view, in section, taken along line 66 of FIG. 5.

Referring now to the figures, it is seen on FIG. 1 that the neck mold assembly referred to generally at 10, includes a thimble or guide ring 11 for guiding the openmg and closing of a partible neck ring 12. FIG. 1 illustrates a first form of the invention. Neck ring 12 opens and closes about parting line A, which is the mold seam line for the neck finish of the container, and is guided in this movement by the flange 11a which fits in the an nular groove 13 of the neck ring arm 14. The neck ring arm 14 is connected at lug 14a as part of the neck ring arm assembly 15 operated by the turret mechanism (not shown) of the glass forming machine, in the conventional manner.

Axially adjacent the guide ring 11 is a guide ring bushing 16 for locating the position of the guide ring 11. The guide ring 11 is rigidly fastened to the bushing 16 by studs 17 threaded into its flange 11a. The bushing 16 is mounted on transfer arms 18 of the turret of the machine. The turret operates in sequence between a blank station, where a gob of molten glass is received and pressed to a parison in a blank mold by a plunger that reciprocates in and out of the center bore of the bushing 16, guide ring 11, neck ring 12 and while held at its pressed neck finish by the neck ring .12, and enclosed in a partible blow mold 19 closed along its parting line, indicated at A. A blow head assembly .20, which includes a blow head casing 21 and blow air tube 22, is lowered onto the top of bushing 16 to onclose its open end and injects the blow air tube 22 into the hollow portion of the parison. Air under pressure isconnected into the blow head casing 21 and tube 22 and the body the parison is then blow formed to its finished shape B. During blowing, a pressure is built up on the interior space in the bushing. Some of the air is flushed therefrom by leakage past the blow head casing 21 and the top of the bushing 16, as. indicated by the arrows on FIG. 1. It is preferred also, as part of the present invention, to utilize some of this blow 'air for circulation past the neck rings glass contacting surface by means and in a manner to be presently described.

In FIG. 2, a second form of the apparatus of the invention is presented. Guide ring 11 has a plurality of holes 23 bored laterally vertically throughits vertical wall portion 24. This forms a means defining a fluid passage through the guide ri'ngfor conducting fluid to an annular channel lying under flange 11a, to be presentmanner in which the neck ring 12 is assembled. In other words, the parting line A for the neck ring, which is the mold seam diameter, will lie 90 from this aforementioned normal diameter when the neck ring is assembled to the guide ring. 7

In FIGS. 3 and 4, the neck ring.120 and guide ring 11 are shown assembled to make up the neck mold assembly 10. When the neck ring 120 is closed about the guide ring 11 there is defined an annular channel 25 therebetween, which extends in endless fashion around the outer vertical surface of the guide walls vertical wall portion 24. The bored holes 23 will, thusly, communicate with the annular channel 25.

A hardened metal insert 26 is generally provided at the lower end of the glass contactingsurface of the neck rings 120 and adjacent vertical passages 27 therein. This insert is most generally of a hardened alloy of metal and its use is known and understood in the glass forming art. In each half of the neck ring 120 are drilled two vertical holes 27. In this particular formof the invention, the holes are drilled as close as permissible to the hardened inserts 26 so as to be practically contiguous with it opposite its glass contacting surface. The holes 27 are drilled to a suflicient height so that they extend opposite the annular channel 25. Corresponding horizontal holes 28 are bored to connect the annular channel 25 with the holes 27.

As shown on FIG. 4, the holes 27 and corresponding holes 28 are spaced equal radial distances measured from the central axis of the neck mold assembly 10. In determining the positioning of the air circulating passages 27, they should be disposed at least 45 ofl of the mold seam diameter. They may be equally spaced apart and their centers on equal radii measured from the center axis of the neck ring, but it is contemplated that they may be otherwise arranged to gain advantages in neck mold cooling.

The spacing of the holes 27 along the neck ring 120 is an important feature of the invention and should be kept within a critical range, as will now be described. The number of fluid passages as holes 27 will depend upon the type of neck finish for the jar being formed.

tered on the diameter thereof normal to its mold seam.

Their location should be confined within an annular zone that has its center on the diameter normal to the mold seam A and its end extremities are at least 45 oli the mold seam. In this connection, the minimum span of the zone to which the cooling fluid has been applied and been found to' operate satisfactorily is a zone spanning an arc of about 5 at each half of the neck ringand cen- It is believed that the maximum span of the zone that will be effective is a zone spanning an arc of about at each neck ring half and centered on this said normal diameter. If the zone exceeds this latter-mentioned arc, it will tend to add to the cooling rate existing at the mold seam area, which will tend to have an unbalancing effect on cooling the finish and tend to intentionally promote an out-of-bound condition of the formed neck finish.

As'shown on FIG. 4, two holes'are drilled on centers that are inch from eachside of a-horizontal centerline normal to the moldseam A and at a radius of 1% inches. To put it another way, the ratio of this radius measured to the center ofthe holes 27 to the spacing between their centers is approximately '1 to 1.

Referring now to F163. 1 and 4, blowing air is circulated vertically of the neck ring and adjacent its glass contacting surface'in the following manner. Final blow air for blow forming the parison enters the bored holes '23 in guide ring 11 and is conducted to the annular chamber 25 where it is circulated thereabouts to the horizontally bored holes 28 in the neck ring, thence to the connecting vertically bored holes 27. This circulation of air, as his directed through the neck ring, cools the metal of the neck ring and its colmonoy insert. In this manner, the mold around the holes 27 will be cooled and thereby extract heat from the glass at that zone at a faster rate and will compensate for the higher rate of heat extraction, as previously pointed out herein, that occurs adjacent the mold seam.

By using blo'wing air to circulate to cool the neck ring, as mentioned above, increases the flushing action of the blowing air in the blow mold and will increase the cooling of the glass being formed in the blow mold. This is an advantageous feature.

A third form of the invention is presented by FIGS. 5 and 6. Here, the guide ring 11 is provided with obliquely bored holes 2'3abeginning at the inner surface of the guide ring 11 opposite-its flange 11a and ending at the external vertical surface thereof under the flange. When the neck ringlZl is closed about the guide ring 11 along parting line A, an L-shaped annular channel 25a is defined under flange 11a. Bored holes 23a communicate with channel 25a (FIG. 6) to connect blowing air to it, as before. The vertical holes 27a are bored in the neck ring adjacent its glass contacting surface to communicate with the annular chamber 25a. In this form of the in- 'vention, the horizontal holes 28 described for the first described embodiment of the invention, are no longer necessary, due to the manner in which the neck ring and guide'ri-ng are'fitted together to define the L-shaped channel 25a.

This neck mold assembly illustrates a diiferent spacing arrangement of the vertically bored holes 27a. They are bored three in each half section of the neck ring and are spaced in comparable zones centered on the diameter D. Thecent-ral hole 27a in each neckring half is centered on the diameter and'one hole 27a: is spaced on either side of this centrally located hole. This is a preferred arrangement of the bored holes for forming a different design of wide mouth container neck finish. The holes 27a are of the order of A3 inch in diameter and drilled on inch centers which are at a radius of 1 inches from the central axis of the neck mold assembly 10. To put it another way, the ratio of this radius to the spacing between the centers of the holes is approximately 4 to 1.

it should be obvious that the closer the fluid passages (27 or 27a) are to the glass contacting surface of the neck ring 12, 120 or 121 the faster the rate of extraction of heat from glass that may be achieved. Moreover, it should be obvious that in practicing the method of the invention, fiuid may be circulated in the zones spelled out and directed thereat against the outside surface of the neck ring Whenever conditions make it practical. Likewise, it is contemplated that where, for this purpose, machined or other defined fluid passages are provided in the neck ring structure they may in certain circumstances be bored obliquely toward or away from the plane of the glass contacting surface of the neck ring to compensate for difierentials in heat conductivity characteristics between metals of the mold, such as between cast steel or iron and colmonoy.

It is suggested, however, that much is to be gained by using blow air for cooling the prescribed zones of the neck ring in that this increases the flushing action of the air used for blowing and consequently increases cooling internally of the container being formed.

Having illustrated three specific examples of the invention by which it may be practiced eifectively, it will, of course, be understood that various details of construction may be modified through a wide range without departing from the principles of this invention, and it is, therefore, not the purpose to limit the patent granted hereon other- Wise than necessitated by the scope of the appended claims.

I claim:

1. A neck mold apparatus comprising a partible neck ring and cooperating guide ring, said neck ring being operable for opening and closing along a diameter of the guide ring, and said neck ring when closed about the guide ring defining an annular channel therebetween, means defining a fluid passage through the guide ring communicating with said channel to form a connection to the channel from the interior surface of said guide ring, at least one passage in each partible portion of said neck ring in a zone located radially and centrally thereof disposed at least 45 from the mold seam, said passages extending axially of said neck ring and in communication with said channel to provide cooling to the neck ring in said zone.

2. The apparatus defined in claim 1, wherein each neck ring half, which spans two quadrants of a circle from seam to seam, has a plurality of said passages in each half of the neck ring between seams, said passages being spaced substantially equal circumferential distances in adjacent one half portions of each of the adjacent quadrants of each neck ring half.

3. The apparatus defined in claim 1, wherein a pair of passages are provided in each half of the neck ring, angularly spaced distances apart in the range of '45-5 degrees measured from the central axis of the neck mold and each spaced substantially equal distances from the mold seam.

4. The apparatus defined in claim 1, wherein the said passages provided in each half of the neck ring have their centers spaced on equal radii from the central axis of the neck ring and are located at least 45 from the mold seam.

5. Apparatus defined in claim 1, wherein two passages are provided in each half of the neck ring, their centers being on equal radii measured from the central axis of the neck ring and on spaced centers which have a ratio of the said radii to the distance between them of approximately 1 to 1.

6. The apparatus defined in claim 1, wherein three passages are provided in each half of the neck ring, their centers being on equal radii measured from the central axis of the neck ring and on equally spaced centers which have a ratio of the said radii to the distance between them of approximately 4 to l.

7. A partible neck mold apparatus which provides for control of the symmetry of dimension of a glass neck finish molded therein comprising, a pair of complementary partible neck ring halves operable to assume a closed juxtaposed relationship about a guide ring on a common diameter and defining a molding cavity for a neck finish portion of a glass container, an annular channel defined between the guide ring and the closed neck ring, means adapted for supplying a coolant fluid to said channel, axially disposed coolant passages in said neck ring halves each of which are connected to said channel, said passages being arranged in close proximity to the glass contacting surface of the neck ring in complementary, diametrically opposed, circumferentially disposed zones on said neck ring, the center of each said zone being located on a diameter of the closed neck ring displaced from said common diameter whereon said neck ring is closed, the extremities of each said zone extending not more than 45 on either side of the said center of that zone, said passages conducting coolant supplied thereto axially of the neck ring to provide for cooling the neck ring in said opposed zones.

References Cited in the file of this patent UNITED STATES PATENTS 215,869 Bodine May 27, 1879 1,798,136 Barker Mar. 31, 1931 2,198,750 Winder Apr. 30, 1940 2,442,315 Samuelson et al. May 25, 1948 2,467,000 Samuelson Apr. 12, 1949 2,550,140 Dotson Apr. 24, 1951 2,645,059 Rowe July 14, 1953 

